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Ignition Control Moduel keeps going bad!!!

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Old 03-04-2015, 02:33 PM
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Ignition Control Moduel keeps going bad!!!


I wasn’t sure where I should post this so I am posting it ina couple different topics….. I have been having trouble with my ignitioncontrol module. I am aware that they are know to go out in our Third Gen’s butits getting a bit ridiculous. I have had to replace my ICM three times in thelast 5 month. They aren’t hard to replace and I keep an extra one in the car atall times, just a few screws I’ve had to replace it on the side of the road soits not a big deal just annoying.

So here is my question… is there something else that couldbe causing my ICM to go bad so often?? Any help would be appreciated.
Old 03-04-2015, 08:39 PM
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Re: Ignition Control Moduel keeps going bad!!!

Are you sure the ICM is going bad? I have seen intermittent pickup coils where you replace the ICM and it'll run again for a while. Are the screens in the bottom of the distributor free of debris and clear? Are you using proper thermal paste on the ICM or using that clear silicone grease that is supplied with new ICMs (BAD!)? Is engine grounded properly? How clean are distributor mounting points and securing hardware? This is how the distributor gets its ground, bad ground can cause ICM to fail prematurely. Some people run an independent ground to the distributor to solve this issue.
Old 03-04-2015, 09:24 PM
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Re: Ignition Control Moduel keeps going bad!!!

Originally Posted by morgsie
Are you sure the ICM is going bad? I have seen intermittent pickup coils where you replace the ICM and it'll run again for a while. Are the screens in the bottom of the distributor free of debris and clear? Are you using proper thermal paste on the ICM or using that clear silicone grease that is supplied with new ICMs (BAD!)? Is engine grounded properly? How clean are distributor mounting points and securing hardware? This is how the distributor gets its ground, bad ground can cause ICM to fail prematurely. Some people run an independent ground to the distributor to solve this issue.
ok thank you very much!! ill look into all these things. I was planning on replacing the coil as a first step though. but thanks again all great advice!
Old 03-05-2015, 09:22 AM
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Re: Ignition Control Moduel keeps going bad!!!

Buy a good ACDELCO ICM. I kept going through them too until I bought a decent one. The cheap ones fail quickly.
Old 03-06-2015, 01:22 PM
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Re: Ignition Control Moduel keeps going bad!!!

Before you REPLACE the coil, how about TESTING it, first?

You'll want to verify the primary resistance, and the secondary resistance.

If the primary, especially, is partially-shorted, the ignition module can't deliver enough current--so it toasts.
Old 03-10-2015, 11:18 PM
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Re: Ignition Control Moduel keeps going bad!!!

While not a bad idea, I like to get the engine heat soaked then test the coil. FWIW, I was referring to the pickup coil in the distributor in my post above...
Old 03-20-2015, 02:58 PM
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Re: Ignition Control Moduel keeps going bad!!!

Agree, get an ACDelco ICM, not parts store clone. Be forewarned, ACDelco part is MUCH more expensive. Last time i burned up an ICM, I switched to an external coil to reduce heat in the distributor. Probably didnt need to, but I felt better.
Old 03-20-2015, 08:41 PM
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Re: Ignition Control Moduel keeps going bad!!!

I remote mounted my ICM on the passenger fender in my caprice. bolted it to a 1/2" thick piece of aluminium, even cut cooling fins on one side of it with a table saw!
Old 03-20-2015, 08:46 PM
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Re: Ignition Control Moduel keeps going bad!!!

Originally Posted by morgsie
I remote mounted my ICM on the passenger fender in my caprice. bolted it to a 1/2" thick piece of aluminium, even cut cooling fins on one side of it with a table saw!
1. Complete waste of effort. The ignition module was designed to live in the distributor. Leaving it there will not hurt anything.

2. By removing it from the protection of the in-distributor mounting, you've potentially exposed it to humidity/moisture that may promote corrosion.

3. For those who insist on moving the ignition module, AC Delco makes a cute little heat-sink that with minor rework will dissipate all the heat the module can develop.

Amazon.com: ACDelco 10474610 GM Original Equipment Igniter Heat Sink: Automotive Amazon.com: ACDelco 10474610 GM Original Equipment Igniter Heat Sink: Automotive
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